Structural performance of reinforced concrete beams with self-healing cover zone

In the current study, experiments were carried out to investigate the structural performance of reinforced concrete (RC) beams with a self-healing cover zone. The cover zone consists of a 1.5-cm-thick layer of bacteria-embedded strain hardening cementitious composite (SHCC) for a combination of crack width control and crack healing. The aim is...

Microstructural characterization of crack-healing enabled by bacteria-embedded polylactic acid (PLA) capsules

The current study investigates short-term and long-term crack-healing behaviour of mortars embedded with bacteria-based poly-lactic acid (PLA) capsules under both ideal and realistic environmental conditions. Two sets of specimens were prepared and subjected to different healing regimes, with the first set kept in a mist room for varying...

Bio-Based self-healing mortar

This paper investigates the effects of alkaliphilic spore-forming bacteria of the genus Bacillus on the compressive strength of the mortar cube and the healing capacity of the bacteria as healing agent on mortar containing crack. The experiments were carried out using cube test, stereomicroscopy and environmental scanning electron microscopy ...

CoRncrete: A corn starch based building material

Starch is a natural polymer which is commonly used as a cooking ingredient. The renewability and bio-degradability of starch has made it an interesting material for industrial applications, such as production of bioplastic. This paper introduces the application of corn starch in the production of a novel construction material, named CoRncrete...

Selection of Nutrient Used in Biogenic Healing Agent for Cementitious Materials

Biogenic self-healing cementitious materials target on the closure of micro-cracks with precipitated inorganic minerals originating from bacterial metabolic activity. Dormant bacterial spores and organic mineral compounds often constitute a biogenic healing agent. The current paper focuses on the investigation of the most appropriate organic...

The Use of Alkaliphilic Bacteria-based Repair Solution for Porous Network Concrete Healing Mechanism

Bacteria induced calcium carbonate precipitation based on metabolic conversion of nutrients has been acknowledged for having potentials in self-healing cement-based materials. Recent studies have shown the development of bacteria-based repair solution (liquid) for concrete surface repair. This article demonstrates the feasible application of...

Chloride transport under compressive load in bacteria-based self-healing concrete

An experiment was carried out in this study to investigate the effect of compressive load on chloride penetration in self-healing concrete containing bacterial-based healing agent. Bacteria-based healing agent with the fraction of 2 mm – 4 mm of particles sizes were used in this contribution. ESEM was applied to study samples which were taken by...

Preparation and optimization of bio-based and light weight aggregate-based healing agent for application in concrete

The innovative technology of self-healing concrete allows the material to repair the open micro-cracks that can endanger the structure’s durability, due to ingress of aggressive liquids. Various concepts of self-healing concrete use encapsulation techniques, in order to immobilize and protect the healing agent during mixing and setting. In this...

ESEM-BSE coupled with rapid nano-scratching for micro-physicochemical analysis of marine exposed concrete

Ordinary Portland cement (OPC) mortar specimens submerged in sea-water were analysed through environmental scanning electron microscopy (ESEM) in back scattered electron (BSE) mode and nano-scratching. Results from both sets of analysis show the presence of distinct phases associated with aragonite, brucite and cement paste. Phases associated...

Performance of shcc with bacteria for concrete patch repair

The overall performance of concrete patch repair systems depends on the durability of and compatibility between the concrete substrate and the repair material. This paper investigates the performance of a new type of SHCC material with embedded bacteria as a repair material. The bacteria are a healing agent to enhance the durability of the...

Bacteria-based self-healing concrete to increase durability of structures

Potential of bacteria-based repair solution as healing agent for porous network concrete

Bacterially induced calcium carbonate precipitation has received considerable attention for its potential application in enforcing or repairing construction material. The mechanism of bacterially mediated calcite precipitation in those studies is primarily based on the enzymatic hydrolysis of urea. Besides calcite precipitation, this reaction...

Injecting a liquid bacteria-based repair system to make porous network concrete healed

Bacteria induced calcite precipitation has been proven to be effective in making concrete structure self-healing. In Microlab TU Delft, the concept has been enhanced by developing a liquid bacteria-based concrete repair system. The solution contains calcite precipitating bacteria, nutrients and buffer compound which may demonstrate high...

Injecting a liquid bacteria-based repair system to make porous network conrete healed

Bacteria induced calcite precipitation has been proven to be effective in making concrete structure self-healing. In Microlab TU Delft, the concept has been enhanced by developing a liquid bacteria-based concrete repair system. The solution contains calcite precipitating bacteria, nutrients and buffer compound which may demonstrate high...

Potential of bacteria-based repair solution as healing agent for porous network concrete

Bacterially induced calcium carbonate precipitation has received considerable attention for its potential application in enforcing or repairing construction material. The mechanism of bacterially mediated calcite precipitation in those studies is primarily based on the enzymatic hydrolysis of urea. Besides calcite precipitation, this reaction...

Recent advances on self healing of concrete

In this paper an overview is given of new developments obtained in research on self healing of cracks in cement based materials and asphalt concrete. At Delft University various projects are running to study self healing mechanisms. The first project that is discussed is Bacterial Concrete, in which bacteria are mixed in concrete, that can...